In recent years, mobile bodies such as an automobile have a radar device for measuring a relative distance, a relative velocity, and the like of an object around the mobile body, based on an electromagnetic wave radiated, and a reflected wave caused by the electromagnetic wave reflected from the object. Some of such radar devices provided in mobile bodies such as an automobile analyze the electromagnetic wave and the reflected wave, thereby recognizing whether an object around the mobile body is a three-dimensional object having a height that may cause an accident in which the vehicle collides with the object, or a road surface static object such as a manhole cover having a height that will not cause an accident in which the vehicle collides with the object, for example. As an example of such apparatuses, Patent Literature 1 discloses a front obstacle detection device (hereinafter, referred to as a conventional technique).
The conventional technique, for example, detects a preceding vehicle going ahead of the vehicle and an object in front of the vehicle, and if it has been determined that the preceding vehicle has travelled over the front object, recognizes the front object as a road surface static object as described above. In addition, if the preceding vehicle is present ahead of the front object, the conventional technique recognizes the front object as a road surface static object as described above. In addition, if the velocity of the vehicle is equal to or greater than a predetermined threshold value and if the front object is present between other two front objects that are continuously detected (for example, guard rails on the both sides of a road where the vehicle is travelling), the conventional technique recognizes the front object as a road surface static object. In addition, after the intensity of a reflected wave from the front object has monotonically increased in accordance with the distance to the front object relative to the vehicle, if it has been determined that the intensity monotonically decreases, the conventional technique recognizes the front object causing the reflected wave as a road surface static object.